textproduct: Rapid City

KEY MESSAGES

-Chance for thunderstorms today, mainly across south central SD, isolated severe weather will be possible there this evening

-Drier pattern as NW flow becomes established

-Seasonal temperatures most of the this week, warmer toward the end of the week

DISCUSSION

(This Afternoon Through Sunday) Issued at 1113 AM MDT Mon Aug 24 2026

NW upper level flow will become established through the end of the week behind today's shortwave. This will support drier weather as deeper moisture shifts south of the FA. One more round of TS expected this afternoon, with a few weaker cells possible early on the central/southern BH before deeper convection potentially develops over scentral SD INVOF of the sfc trough. Deep layer shear will increase across southern SD as the mid level speed max pushes into the region. This will allow a few strong to severe cells with large hail/damaging winds being the main threat. Things will dry out and shift east overnight. There may be a few elevated showers later tonight across the sw third as a secondary wave pushes the region. Have left some low pops for this overnight into Tue morning. Dry most places Tue. The only exception will be the central and southern BH where enough residual moisture may be in place for isold shra/ts in the afternoon. Same for Wed as a weak impulse with sufficient LL moisture may once again support a shower or storm in the afternoon there and the northeast WY Plains. Flow will transition to more westerly by the end of the week with warmer temps by Friday when widespread 90s are expected. Semi-unsettled this weekend with SW flow aloft and sufficient LL moisture in place. However,the better chances for rain look to be north of the FA as a stronger upper trough tracks across MT into ND Sunday.

AVIATION

(For the 18Z TAFS Through 18Z Tuesday) Issued At 1114 AM MDT Mon Aug 24 2026

Thunderstorms are expected to form around 24/20z across the Black Hills, with additional development across the southwestern SD plains through the afternoon and evening. Transient MVFR/IFR conditions are expected in any storms, although coverage of storms will be spotty. Conditions will improve starting around 25/05z. Outside of storms, VFR conditions will persist through the forecast period.

UNR WATCHES/WARNINGS/ADVISORIES

SD...None. WY...None.